Numbers k such that k prefixed by '3' and followed by '9' is prime.

Terms

a(0) =4a(1) =5a(2) =7a(3) =8a(4) =10a(5) =11a(6) =16a(7) =20a(8) =22a(9) =25a(10) =29a(11) =31a(12) =32a(13) =35a(14) =38a(15) =44a(16) =46a(17) =49a(18) =52a(19) =53a(20) =55a(21) =65a(22) =70a(23) =71a(24) =73a(25) =76a(26) =77a(27) =88a(28) =91a(29) =92